VIX - any other mean reverting indices

Does anyone else know of any other mean reverting indices out there that have trade-able products like the VIX?
I know there are other VIX's - oil, gold, etc. but I'm not sure if a retail investor can trade these.

Basically I'm wondering if there is another mathematical measurement like the VIX that can be traded by a retail investor.

Does anyone else know of any other mean reverting indices out there that have trade-able products like the VIX?
I know there are other VIX's - oil, gold, etc. but I'm not sure if a retail investor can trade these.

Basically I'm wondering if there is another mathematical measurement like the VIX that can be traded by a retail investor.

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the mean of anything is Flux remember that! and as well know the risks of ETF's that derive their values from futures contracts...